The title "English installer" and "International installer" is somewhat misleading -- the only difference between them is that the English installer uses InstallShield and does not require that Java 1.3 is used, whereas the International installer uses InstallAnywhere and installs Java 1.3 (and enforces that LimeWire use it). You'll actually see better performance if you install an international JRE of Java 1.4 or higher and use the English installer. We're exploring ways to update the international installer.
You can help us improve the translations by going to
http://limewire.org/translate.shtml and seeing how to submit newer translations. The Spanish translation is only 65.22% complete right now -- any help we can get to raise that number would be much appreciated.